Chip Ganassi Racing driver Kyle Larson dropped to second in the NASCAR Cup standings after NASCAR docked him 35 points and suspended crew chief Chad Johnston for three races after an illegal rear brake cooling assembly was found in Larson's second-place car from the race Saturday at Kentucky Speedway.

Larson had held a one-point lead on Martin Truex Jr. in the standings, but the penalty now puts him 34 points behind. The penalty could be big when it comes to the playoffs. The regular-season champion earns 15 extra playoff points, while the second-place finisher gets 10 extra playoff points when the points are reset in the each of the first three rounds of the postseason.

Chip Ganassi Racing will not appeal, a team spokesman said, and Johnston will serve his suspension at upcoming races at New Hampshire, Indianapolis and Pocono. No interim crew chief was immediately announced.

Kyle Larson went from first to second in the standings after being docked 35 points. Jerry Markland/Getty Images

"We accept the penalty and will move forward," the team said in a statement.

NASCAR found the violation during its Tuesday inspection of select cars -- it always takes first-place and second-place cars among them -- at its technical center in North Carolina. It determined that Larson's car violated the rule that prohibits duct work or other devices to pass from one area of the interior of the vehicle to another or to the outside of the vehicle.

Manipulating the way the air flows underneath the car can impact how it handles through the turns. Larson twice nearly drove through the field Saturday night at Kentucky. He had started in the rear because his car didn't pass prequalifying technical inspection. He then returned to the rear for a speeding penalty on pit road. The only driver he couldn't catch at the end of the race was Truex, who earned his third victory of the season.